Self locking mast assembly and method of making

ABSTRACT

A mast arrangement having two elongate individual masts. The first elongate individual mast comprises a hollow connector comprising an inner diameter. The second elongate individual mast comprises a protruding connector end. The protruding connector end telescopically engages with the hollow connector end. The mast arrangement also comprises a pin and slot arrangement and collars to connect the masts together and minimize unwanted disengagement of the masts from each other.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.12/378,874, filed on Feb. 20, 2009, and has been issued as U.S. Pat. No.7,980,781, issued on Jul. 19, 2011.

BACKGROUND

Technical Field

The present invention has to do with a much needed improvement of thetools used in the field of commercial nuclear power plants. Nuclearreactors have a reactor core made up of a number vertically positionedand elongated fuel rod bundles that provide the necessary nuclearmaterials or elements to heat water circulating the fuel bundles. Whenthe fuel rod bundles have been depleted their nuclear materials aretermed “spent” and a re-fueling of the reactor core must be performed.In re-fueling or maintenance the “spent” bundles are removed from thereactor core, remaining still useable “unspent” bundles are repositionedto the center of the reactor core, and new fuel rod bundles are added tothe radially outer dimensions of the reactor core. Each fuel bundle hasa relatively confined cavity space into which it must fit as it existsalongside the other vertically positioned bundles. The positioning ofthe new fuel bundles and the re-positioning of the unspent bundlesrequires tools that provide a manual dexterity to the workers. Thebundles must be positively connected on the bottom of the reactor andtheir correct attachment and alignment is a critical part of there-fueling operation. Because the water level of the reactor core is notdrained and the water is not cooled for the re-fueling operation,special tools are required for the removal, insertion and cleaning ofthe bundles and cavities of the reactor core. Very special tools alreadyhave been developed for the removal, insertion and placement of the fuelbundles, but in addition to those tools there are other tools that arenecessary for performing maintenance while the bundles are removed andbefore they are replaced. Maintenance workers extend tools into thewatery cavities in order to perform a variety of required tasks andthese tools usually comprise elongate, segmented, hollow poles, referredto as masts. On the distal end of the masts are attached tools that maybe of the gripping, wrenching, rotating, or brushing type, and if theyare pneumatically operated, usually have their air supply hoses extendalong the exterior length of the masts. When using such segmented mastsit is very important that the masts do not become disconnected from oneanother when being twisted and turned by the workers and further thatthey do not introduce any foreign materials to the reactor core. Incurrent practices the existing segmented masts may be joined by threadedconnections or pinned arrangements and duct tape is commonly used overthe jointed section to aid in holding the masts together or intactduring use. Duct tape is certainly not strong enough and creates thepossibility of introducing its own foreign material into the reactorcore. Duct tape also does not positively prevent any broken pins,springs, or other material failures from contaminating the core. Foreignmaterial in the core area is extremely undesirable.

BRIEF SUMMARY OF THE INVENTION

It is an object of the present invention to provide a means toreleasably attach separate individual elongate members to one another.

It is an object of the present invention to provide a releasable lockingconnector between individual pole segments.

It is an object of the present invention to provide co-operatingelements of a self contained telescopic locking arrangement forindividually separable pole segments.

It is an object of the present invention to provide a lockingarrangement for telescopically engaged pole segments that holds thesegments locked in relation to one another during use.

It is an object of the present invention to provide a toolingarrangement for the nuclear industry that provides a reliable andreleasable locking connection for segmented poles used to extend toolsinto reactor cores.

It is a still further object of the present invention to provide asegmented pole locking arrangement where the individual locking elementsare self-contained such that upon the failure or breakage of a lockingpart it will not contaminate the working environment.

It is a further object of the present invention to provide a reliableconnector between mast poles so that tools may be extended into remoteareas without the mast poles becoming disconnected.

It is a further object of the present invention to provide a reliableconnection between mast poles so that tools may be extended into hostileenvironments without the mast poles becoming disconnected.

This invention has to do with a locking connector for two members havingseparable telescopic engagement with one another. The arrangementcomprises first and second elongate individual members with a hollow endon the first member and a protruding reduced dimension end on the secondmember for telescopic engagement with the hollow end on the firstmember. A releasable co-operating pin and slot engagement arrangement,between the hollow end and the reduced end, provides for movement of theindividual members from a first position to a second position. The firstposition allows the hollow end and the reduced end to be moved axiallyinto and out of telescopic engagement with one another and the secondposition allows the members to be held in a non-movable in relation toone another. A pair of co-operating locking collars on one of theconnector ends provides the means for releasably locking said pin andslot engagement in said second position.

The invention further comprises the method of making the individualconnector ends according to the structure described and then attachingthem to the ends of mast poles that are without the connections. Theconnector ends are furnished with weld attachment surfaces and weld prepareas so that they may be added to masts already existing in the field.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective of the connector disconnected according to thepresent invention.

FIG. 2 is a side view of the connector locked according to the presentinvention.

FIG. 3 is a side view of the upper collar retracted of the connectoraccording to the present invention.

FIG. 4 is a side view of the lower collar in relation with the uppercollar of the connector according to the present invention.

FIG. 5 is a side view with a second connector raised to begin removalfrom first connector according to the present invention.

FIG. 6 is a cross section view of the connector in the locked positionaccording to the present invention.

FIG. 7 is a cross section view of the upper collar retained of theconnector according to the present invention.

FIG. 8 is a transverse cross section 8-8 through FIG. 2 of the connectorend according to the present invention.

FIG. 9 is a transverse cross section 9-9 through FIG. 2 of the connectorend according to the present invention.

FIG. 10 is a transverse cross section 10-10 through FIG. 7 of theconnector end according to the present invention.

FIG. 11 is a perspective view of a portion of the collar 32 of thepresent invention.

FIG. 12 is a longitudinal cross-sectional view 12-12 of the portion ofthe collar 32 in FIG. 11.

DESCRIPTION OF EMBODIMENT OR EMBODIMENTS

What is shown in FIG. 1 the self-locking mast assembly 10 according tothe present invention. The mast assembly 10 has a first mast connectorend 12 that has a hollow diameter telescopic engagement section 14 thatextends inwardly from an abutment surface 15 located on a distal end ofthe mast connector end 12. The hollow diameter section 14 is shownhaving a J shaped slotted portion 16 on diametrically opposite sides ofthe telescopic section 14. The J shaped slot 16 is formed having a shortleg as is shown at 18, a cross leg of the slot as is shown at 20 arid apin communicating slot as is shown at 22. A knurled section 24 isprovided on the hollow diameter section 14 and is an aid for a personhand gripping the mast connector end 12. A second mast connector end isshown at 26 and has a telescopic engagement diameter portion which issized for co-operating engagement with hollow diameter section 14. InFIG. 1 telescopic diameter portion 28 has a reduced diameter from boththe mast connector end 26 and telescopic section 14. The reducedtelescopic engagement diameter section 28 has a pin 30, which extendsthrough the diameter of the reduced diameter section 28 and protrudesradially above and outward on diametrically opposite sides of thetelescopic engagement diameter portion 28. A first collar 32 is shownlocated on the second mast connector end 26 and (as will be seen later)the collar 32 is spring loaded so that is biased toward the pin 30 andinto abutment with a second collar 34 on the second mast connector end26. The collar 32 is also slidable linearly along a portion of thelength of the mast connector end 26 and is partially rotatable aboutsaid mast connector end 26. The second collar 34 is located adjacent tothe first collar 32 and the second collar 34, as will be seen later, isthreadedly mounted on the diameter of second mast connector end 26 sothat it is rotatable about the mast connector end 26, but not slidablealong its length. The collar 34 is mounted on and threadedly engagedwith mast connector end 26 so that it can be threadedly rotated so thatit advances towards the pin 30 or away from the pin 30. Numbers 36 and38 represent the cooperating elements of bevel engagement between theabutting ends of the two collars 32 and 34. The co-operating elements ofbevel engagement 36 and 38, when in spring loaded abutting relation andengagement with one another, form a one way locking action between thetwo collars 32 and 34. The locking action occurs because the bevels 36and 38 are angled in such a way that the collar 34 can be rotated so asto advance toward pin 30 and the engaged bevels 36 and 38 will allowrelative rotation (ratcheting) between the engaged collars 32 and 34.The angle on the bevels will not allow collar 34 to be rotated in theopposite direction so as to advance away from pin 30. In the fullyassembled and locked position collar 34 has its abutment surface 17fully abutted against abutment surface 15 of connector end 14 and socannot rotate any further in that direction. On the other end collar 34has its bevels engaged with the bevels on collar 32 and the angled teethof the bevels prevent any relative rotation of collar 34 in the oppositedirection. In this manner is the connecting arrangement said to beself-locking when placed into full engagement. Wrench flats 200 areshown on collars 32 and 34 for ease of disassembly. While the connectorends 12 and 26 are shown the connector end 12 has an end 104 that isused to connect to a mast pole. For the purposes of this description theterm mast is used to mean an elongate pole. The masts 100 are usuallyhollow but do not necessarily have to be. In this illustration the mastpole will have a weld prep end 102 that is joined to a weld prep area112 on connector 12. The weld joint is shown at 106 and is the usualmeans of connecting the mast poles to both of the connector ends 12 and26. The connector end 26 has a similar mast connector end as 12.

What is show in FIG. 2 is the self-locking mast assembly 10 showing themast connector end 12 as it is fully engaged and connected in aself-locking manner to the mast connector end 26. The first mastconnector end 12 has the hollow diameter section shown at 14 with the Jslot 16. The pin 30 is shown engaged in the short leg 18 of the J slot16. The second mast connector end 26 has its reduced diameter portion 28engaged with and fully enclosed within the hollow diameter telescopicsection 14 of the first mast connector end 12. The second mast connectorend 26 is shown having the first and second collars 32 and 34 fullyengaged through their co-operating locking bevel elements 38 and 36respectively. The second collar 34 has been rotated on the threadsprovided on the second mast connector end 26 so that it is fullyabutting the end 15 of the hollow diameter section 14. The first collar32 is spring loaded or urged into engagement with the second collar 34and the cooperating elements of locking bevels 36 and 38 are engaged sothat relative rotational movement may only take place in one directionand may not take place so as to allow the collar 34 to advance away frompin 30. In this manner the two mast connector ends 12 and 26 arefastened together in a self-locking manner, wherein longitudinalmovement between the ends is prevented and relative rotational movementbetween the collars 32 and 34 is prevented in one direction by theengagement of the bevels 36 and 38, and in the opposite direction by theabutment of the collar 34 with the abutment surface 15 on the connectorend 12.

What is shown in FIG. 3 is again the self-locking mast assembly 10according to the present invention, and this time showing a portion ofthe hollow diameter section 14 with the J shaped slot 16. The pin 30 isstill engaged with the short leg 18 of the J shaped slot 16 and thesecond mast connector end 26 still has its protruding section 28telescopically engaged within the hollow telescopic diameter section 14.In FIG. 3 the first collar 32 is shown pulled back against itsspring-loaded direction and latched in place so that the cooperatingelements of bevel engagement 36 and 38 are disengaged. The collar 32 hasenough linear travel, from its forward most spring urged position to itsrearward most position, so that it equals, at least, the linear distanceof the J-shaped slot section 18. Pushing mast connector end 26 towardmast connector end 12 will then move pin 30 (located in telescopicsection 28) into the J-shaped cross section slot 20. Relative rotationof the mast connectors 12 and 26 will then move pin 30 across cross slot20 and into pin communication slot 22. The mast connector ends 12 and 26may then be pulled apart. As can be seen in FIG. 3 when the first collar32 is pulled back against its spring loaded direction, the second collar34 may be threadedly advanced away from the hollow diameter section 14and away from abutment with the end 15 of the hollow diameter telescopicsection 14. It is necessary for the collar 32 to be held against itsspring loaded direction in order to rotate the adjacent collar 34 to itsdesired position and the present invention provides a type of latchingaction that will hold the collar back to enable rotation of collar 34.The latching mechanism cannot be seen in this Figure but is providedbetween the internal slot 82 on the collar 32 and the protruding ends 44of pin 134. The collar 32 is essentially made from two pieces (ReferenceFIGS. 11 and 12) 80 and cap 88. The way that the collar 32 is assembledon the mast connector end 26 requires that piece 80 (Shown in FIG. 11)is mounted on the connector end 26 at its desired location. Spring 132is then loaded into the lower piece 80 of collar 32. Slot 82 then allowsa properly sized hole to be drilled through the diameter of 26 and pin134 fixedly mounted in the hole so that its opposing ends 44 protrudeslightly beyond the inside diameter of the connector end 80. Cap 88 isthen co-joined with the piece 80 by co-axially sliding a portion of itsinner diameter over the slotted area 82 of piece 80. When the two pieces88 and 80 are properly engaged they are then welded together. The collar32 is then able to transverse back and forth along a small axialdistance on the connector end and also able to rotate partially onconnector end as defined by the dimensions of the slotted portion 86 ofslot 82. With this arrangement the collar 32 may be moved back againstits spring urged direction, and upon rotation, the protruding ends 44 ofpin 134 will engage the slotted portion 86 of the piece 80 and be heldback in that position. The collar 32 may be released by rotating thecollar 32 back to its original position where pin 134 will communicatewith the slotted portion 84 of the piece 80.

What is shown in FIG. 4 is the self-locking mast assembly 10 accordingto the present invention showing a portion of the hollow telescopicsection 14 of the first mast connector end 12 as it is still engagedwith the second mast connector end 26. The hollow diameter portion 14 isshown with the J shaped slot 16 still engaging the pin 30 of the reduceddiameter section 28 of the second mast connector end 26. As wasdescribed in FIG. 3 the collar 32 had been pulled back against itsspring urged direction and latched and now 34 has been rotated along itsthreaded portion so that it has advanced away from the abutment surface15 of the enlarged diameter section 14. Enough of a space is providedbetween the abutment surface 17 on collar 34 and abutment surface 15 onthe hollow diameter section 14 such that it is at least equal to orgreater than the linear axial distance of the short leg slot 18 of the Jshaped slotted portion 16. The first mast connector end 12 may be pushedforward such that the pin 30 will be able to traverse the cross leg 20of the J shaped slot 16 and rotated into communication with the pincommunication slot 22.

What is shown in FIG. 5 is the self-locking mast assembly 10 accordingto the present invention showing a portion of the telescopic section 14of the first mast connector end 12 and mast connector end 26. Relativerotation between connector ends 12 and 26 moves telescopic section 14such that the J shaped slot 16 allows the pin 30 to transverse the crossleg 20 of the J shaped slot 16. In this manner, the pin 30 will traversecross-leg 20 and communicate with the pin communication slot 22. Thetelescopic section 14 of the first mast connector end 12 will then beable to be disengaged entirely from the individual second mast connectorend 26.

What is shown in FIG. 6 is a cross sectional view 6-6 of FIG. 2according to the present invention. The self-locking mast assembly 10 isshown connecting the first and second mast connector ends 12 and 26,respectively, to one another. The reduced diameter portion 28 of thesecond mast connector end 26 is shown having the pin 30 therein. Thecollar 34 is shown having the cooperating elements of threadedconnections 35 and 37. The collar 32 is shown having a spring 132mounted on and adjacent to the outer diameter of the second mastconnector 26, and pin 134 is mounted so that it extends through thediametrical sides of the second mast connector end 26 with each of itsouter ends protruding slightly above the diameter of the second mastconnector 26. The spring 132 is located in the internal relief 138 ofthe collar 32 and collar 32 has a spring facing abutment surface 48 thatspring 132 abuts against to urge the collar 32 away from the pin 134.When grasping the collar 32 and pulling it towards the pin member 134the spring 132 will be compressed. The construction of collar 32 as isshown in FIGS. 11 and 12 is shown in some detail in this Figure. As isshown in FIGS. 11 and 12 the collar 32 is shown formed as a two piececonstruction with cap 88 sliding down over piece 80 and welded into afixed engagement as a finally assembled one piece construction collar32. The reason for this is that when assembling the connector end 26 itwas necessary to slide the piece 80 over the connector end 26 until theslot 82 was aligned with the hole in 26 that had been drilled for pin134. Pin 134 is then inserted into its hole in a press-fit type ofengagement. The pin 134 has been sized so that its ends protrudeslightly above the diameter of the connector 26. With the pin 134 inplace the cap 88 is then slid over the end of piece 80 and welded inplace. In this manner the collar 32 and the pin 134 may have relativerotation between one another so that the pin 134 may provide thelatching engagement when pin 134 is rotated into the slot portion 86.When rotated out of engagement with 86 the collar 32 may slide axiallyalong the longitudinal axis of the connector 26.

What is shown in FIG. 7 is a cross sectional view of the self-lockingmast assembly 10 according to the present invention. Collars 32 and 34are mounted on the second mast connector end 26, and collar 32 has aninternal relief 138 which provides an annular space around the diameterof the second mast connector end 26. A pin 134 is inserted through thediameter of mast connector end 26 and has extending ends 44 thatprotrude beyond the diameter of the mast connector end 26. A spring 132surrounds the outer diameter of the mast connector end 26 just adjacentto the pin 134 and is confined by the lip portion 48 of the collar 32.In this way the spring 132 is compressed between the shoulder 136 andthe lip 48 of the collar 32 such that the collar 32 is urged towardengagement of bevels 36 and 38. The collar 34 has cooperating threads 35and 37 with the threads 37 formed on the diameter of the mast connectorend 26 and threads 35 formed on the internal diameter of the collar 34.In this way the rotation of the collar 34 will advance the abutmentsurface 17 towards the engagement pin 30 or away from the engagement pin30 as may be desired.

What is shown in FIG. 8 is a transverse cross sectional view 8-8 of FIG.2 of the mast assembly 10 according to the present invention. Shown inFIG. 8 is the bevel surface 38 on collar 32. Pin 134 is shown extendingthrough the mast 26.

What is shown FIG. 9 is a transverse cross sectional view 9-9 throughFIG. 2 of the mast assembly 10 according to the present invention. Shownin FIG. 9 is pin 30 extending through hollow diameter portion 14 offirst mast connector end 12. Slot 22 is shown formed in opposite sidesof the hollow connector end 14. Collar 34 is shown with wrench flats200.

What is shown in FIG. 10 is a transverse cross sectional view 10-10through FIG. 7 of the mast assembly 10 according to the presentinvention. Shown in FIG. 10 is the pin 134 extending through thediameter of mast 26.

What is shown in FIG. 11 is a perspective view of the collar 32. Thecollar 32 is actually made from two pieces with the first part 80 asshown in FIG. 11. The part 80 is shown with an L-shaped slot 82 formedthrough the sidewall having an axial extending portion shown at 84 and acircumferential extending slot shown at 86. The L-shaped slot is formedon opposite diametrical sides of the thimble like part 80. The part 80will be mounted on the second mast connector end 26 so that the opposingslots 82 will surround the protruding portions 44 of pin 134 that extendbeyond the diameter of 26 as is shown in FIGS. 6, 8 and 10. A tubularcap 88 will then be fitted down over the top part 85 of the piece 80 andthe cap will be welded to portion 80 thereby forming the collar 32. Cap88 is shown in FIGS. 6 and 7. The reason for this arrangement is that inassembling the collar 32, the spring 132 and the pin 134 it will benecessary to insert first the spring 132, then the pin 134, while thepiece 80 is mounted on the mast connector end 26 with the slots 82aligned with the hole drilled through mast connector end 26 that is toreceive the pin 134. When the pin 134 is then inserted the cap 88 maythen be slid down so that its tubular portion covers the slots 82 andthen fixed to part 80 by welding or other equivalent means. Collar 32 isthen limited in its movement about the mast connector end 26 by the twolegs 84 and 86 of the slots 82.

What is shown in FIG. 12 is a view 12-12 through FIG. 11. The part 80 isshown with the bevel teeth 38 and the slot portions 84 and 86.

The connector ends are usually made from an aluminum material and whenthat is the case a further coating and or anodizing process may beemployed to protect the material from any harsh environment that it mayencounter.

Other objects and further scope of applicability of the presentinvention will become apparent from the detailed description; it shouldbe understood however that the detailed description, while indicatingcertain embodiments of the invention, is given by way of illustrationonly, since various changes and modifications within the spirit andscope of the invention will become apparent to those skilled in the art.

1. A mast arrangement comprising: first and second elongate individual masts; said first elongate individual mast comprising a hollow connector end; said hollow connector end having an inner diameter; said second elongate individual mast comprising an elongated body portion; said elongated body portion comprising a protruding connector end; said protruding connector end having an outer diameter; said outer diameter of said protruding connector end being smaller than said inner diameter of said hollow connector end to permit telescopic engagement with said hollow connector end; said hollow connector end comprising a slot arrangement; said protruding connector end comprising a pin with ends; said pin being configured and disposed to extend through said protruding connector end with said ends protruding beyond the smaller, outer diameter of said protruding connector end; said pin being configured to be inserted into said slot arrangement and moved into a final position in said slot arrangement, in which final position said pin engages said slot arrangement to essentially prevent relative rotational movement of said first and second elongate individual masts, and to minimize axial movement of said first and second elongate individual masts away from one another to prevent disengagement of said first and second elongate individual masts; said elongated body portion comprising a threaded portion disposed adjacent said protruding connector end; said second elongate individual mast comprising first and second adjacent collars coaxially mounted on said elongated body portion adjacent said protruding connector end; said first adjacent collar being threadedly mounted on said threaded portion of said elongated body portion; said first adjacent collar being configured to be rotatably, axially moved between a first position in which said first adjacent collar is at a first distance from said pin, and a second position in which said first adjacent collar is at a second, shorter distance from said pin; said first adjacent collar being configured to be moved into said first position to permit insertion of said pin into said slot arrangement, and to permit movement of said pin into said final position in said slot arrangement, and to permit removal of said pin from said final position and out of said slot arrangement; said first adjacent collar being configured to be moved into said second position and into contact with said hollow connector end, upon said pin being in said final position, to essentially prevent movement of said pin from said final position and to minimize relative axial movement of said first and second elongate individual masts to prevent disengagement of said first and second elongate individual masts; said second adjacent collar being axially moveable along said elongated body portion, and being spring mounted on said elongated body portion so as to be urged toward said first adjacent collar and said pin; said first adjacent collar and said second adjacent collar comprising an arrangement to permit rotational movement therebetween in a first direction and inhibit rotational movement therebetween in a second direction, which second direction is opposite said first direction; said second adjacent collar being configured to be temporarily axially moved away from and out of engagement with said first adjacent collar to permit rotational, axial movement of said first adjacent collar away from said pin; and said second adjacent collar being configured to lock said first adjacent collar in said second position to essentially prevent unwanted disconnection of said first and second elongate individual masts from each other.
 2. The mast arrangement according to claim 1, wherein said slot arrangement comprises a pair of slots formed in diametrical opposite sides of said hollow connector end wherein each end of said pin is configured to engage a corresponding one of said slots.
 3. The mast arrangement according to claim 2, wherein said pair of slots comprises a pair of J-shaped slots.
 4. Connectors for joining together elongate mast pole assemblies comprising: a first connector comprising a hollow connector end; said hollow connector end having an inner diameter; a second connector comprising an elongated body portion; said elongated body portion comprising a protruding connector end; said protruding connector end having an outer diameter; said outer diameter of said protruding connector end being smaller than said inner diameter of said hollow connector end to permit telescopic engagement with said hollow connector end; said hollow connector end comprising a slot arrangement; said slot arrangement comprises a pair of slots formed in diametrical opposite sides of said hollow connector end wherein each end of said pin is configured to engage a corresponding one of said slots; said protruding connector end comprising a pin with ends; said pin being configured and disposed to extend through said protruding connector end with said ends protruding beyond the diameter of said protruding connector end; said pin being configured to be inserted into said slot arrangement and moved into a final position in said slot arrangement, in which final position said pin engages said slot arrangement to essentially prevent relative rotational movement of said first and second connectors, and to minimize axial movement of said first and second connectors away from one another to prevent disengagement of said first and second connectors; said elongated body portion comprising a threaded portion disposed adjacent said protruding connector end; said second connector comprising first and second adjacent collars coaxially mounted on said elongated body portion adjacent said protruding connector end; said first adjacent collar being threadedly mounted on said threaded portion of said elongated body portion; said first adjacent collar being configured to be rotatably, axially moved between a first position in which said first adjacent collar is at a first distance from said pin, and a second position in which said first adjacent collar is at a second, shorter distance from said pin; said first adjacent collar being configured to be moved into said first position to permit insertion of said pin into said slot arrangement, and to permit movement of said pin into said final position in said slot arrangement, and to permit removal of said pin from said final position and out of said slot arrangement; said first adjacent collar being configured to be moved into said second position and into contact with said hollow connector end, upon said pin being in said final position, to essentially prevent movement of said pin from said final position and to minimize relative axial movement of said first and second connectors to prevent disengagement of said first and second connectors; said second adjacent collar being axially moveable along said elongated body portion, and being spring mounted on said elongated body portion so as to be urged toward said first adjacent collar and said pin; said first adjacent collar and said second adjacent collar comprising an arrangement to permit rotational movement therebetween in a first direction and inhibit rotational movement therebetween in a second direction, which second direction is essentially opposite said first direction; said second adjacent collar being configured to be temporarily axially moved away from and out of engagement with said first adjacent collar to permit rotational, axial movement of said first adjacent collar away from said pin; and said second adjacent collar being configured to lock said first adjacent collar in said second position to essentially prevent unwanted disconnection of said first and second connectors from each other.
 5. The connectors according to claim 4, wherein said pair of slots comprises a pair of J-shaped slots.
 6. A nuclear reactor tool-carrying mast structure being configured to be extended into a nuclear reactor core comprising: first and second elongate individual masts; said first elongate individual mast comprising a hollow connector end; said hollow connector end having an inner diameter; said second elongate individual mast comprising an elongated body portion; said elongated body portion comprising a protruding connector end; said protruding connector end having an outer diameter; said outer diameter of said protruding connector end being smaller than said inner diameter of said hollow connector end to permit telescopic engagement with said hollow connector end; said hollow connector end comprising a slot arrangement; said protruding connector end comprising a pin with ends; said pin being configured and disposed to extend through said protruding connector end with said ends protruding beyond the smaller, outer diameter of said protruding connector end; said pin being configured to be inserted into said slot arrangement and moved into a final position in said slot arrangement, in which final position said pin engages said slot arrangement to essentially prevent relative rotational movement of said first and second elongate individual masts, and to minimize axial movement of said first and second elongate individual masts away from one another to prevent disengagement of said first and second elongate individual masts; said elongated body portion comprising a threaded portion disposed adjacent said protruding connector end; said second elongate individual mast comprising first and second adjacent collars coaxially mounted on said elongated body portion adjacent said protruding connector end; said first adjacent collar being threadedly mounted on said threaded portion of said elongated body portion; said first adjacent collar being configured to be rotatably, axially moved between a first position in which said first adjacent collar is at a first distance from said pin, and a second position in which said first adjacent collar is at a second, shorter distance from said pin; said first adjacent collar being configured to be moved into said first position to permit insertion of said pin into said slot arrangement, and to permit movement of said pin into said final position in said slot arrangement, and to permit removal of said pin from said final position and out of said slot arrangement; said first adjacent collar being configured to be moved into said second position and into contact with said hollow connector end, upon said pin being in said final position, to essentially prevent movement of said pin from said final position and to minimize relative axial movement of said first and second elongate individual masts to prevent disengagement of said first and second elongate individual masts; said second adjacent collar being axially moveable along said elongated body portion, and being spring mounted on said elongated body portion so as to be urged toward said first adjacent collar and said pin; said first adjacent collar and said second adjacent collar comprising an arrangement to permit rotational movement therebetween in a first direction and inhibit rotational movement therebetween in a second direction, which second direction is essentially opposite said first direction; said second adjacent collar being configured to be temporarily axially moved away from and out of engagement with said first adjacent collar to permit rotational, axial movement of said first adjacent collar away from said pin; and said second adjacent collar being configured to lock said first adjacent collar in said second position to essentially prevent unwanted disconnection of said first and second elongate individual masts from each other.
 7. The nuclear reactor tool-carrying mast structure according to claim 6, wherein said slot arrangement comprises a pair of slots formed in diametrical opposite sides of said hollow connector end wherein each end of said pin is configured to engage a corresponding one of said slots.
 8. The nuclear reactor tool-carrying mast structure according to claim 7, wherein said pair of slots comprises a pair of J-shaped slots.
 9. The nuclear reactor tool-carrying mast structure according to claim 8, in combination with tools of the gripping, wrenching, rotating, or brushing type. 